Rapid and Simple Method for Measuring Petroleum Asphaltenes by the Centrifugation Technique

Area of Science:

• Petroleum Geochemistry
• Analytical Chemistry

Background:

• Asphaltenes, heavy crude oil components, complicate oil flow and emulsion separation.
• Accurate asphaltene measurement is crucial for oil production efficiency and cost management.
• Current standard methods (ASTM, IP) for asphaltene determination are time-consuming.

Purpose of the Study:

• To introduce and validate a novel, rapid centrifugation-based methodology for asphaltene separation.
• To compare the performance of the new method against established gravimetric techniques (ASTM D6560).
• To assess the applicability of the new method across a range of crude oil types with varying API gravities.

Main Methods:

• Modification of the ASTM D6560 gravimetric method by incorporating centrifugation for asphaltene separation.
• Testing the methodology on diverse crude oil samples (API gravity 17.4 to 39.8).
• Evaluation of key performance metrics including time consumption, sample throughput, repeatability, and reproducibility.

Main Results:

• The new centrifugation method significantly reduces analysis time and allows for parallel processing of multiple samples.
• The method demonstrates good repeatability, with maximum values of 8.0% (low asphaltene content) and minimum of 3.75% (high asphaltene content).
• Excellent reproducibility was observed, ranging from a maximum of 17.0% to an ideal 0.0% for samples with high asphaltene content.

Conclusions:

• The centrifugation-based methodology offers a faster, more efficient alternative for asphaltene determination in crude oil.
• This technique is suitable for both laboratory and potential field applications, enhancing operational flexibility.
• The method's strong repeatability and reproducibility make it a reliable tool for the oil industry.